Interlaminar endoscopic lateral recess decompression-surgical technique and early clinical results.

BACKGROUND

Lateral recess stenosis is a common pathology causing de-novo or residual radicular pain following lumbar spine surgery. Diagnostic criteria and treatment strategies for symptomatic lateral recess stenosis are not well established.

METHODS

We identified ten patients in our prospective patient database (n=146) who underwent endoscopic interlaminar decompression for unilateral symptomatic lateral recess stenosis. Lateral recess height and angle were measured on axial T2-weighted MRI. Values from the symptomatic side were compared to the contralateral side which served as asymptomatic control. Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) for back and leg pain were collected preoperatively, postoperatively and at last follow-up.

RESULTS

Preoperative MRI revealed that both lateral recess angle and height were significantly smaller on the symptomatic compared to the asymptomatic side (angle: 19.3° vs. 35.7°; height: 2.9 vs. 5.7 mm; P<0.01). All patients tolerated endoscopic interlaminar decompression well and half of the patients were discharged on the day of surgery. At last follow-up (12.6±1.7 months), 8 out of 10 patients experienced a minimally clinically important improvement of their VAS for ipsilateral leg pain, which improved from 7.2±0.5 preoperatively to 2.5±0.8 postoperatively (P=0.001). The back pain VAS also improved (preoperatively 5.1±1.1 vs. postoperatively 1.7±0.9, P<0.05). The ODI improved from 50±5.8 preoperatively to 22.2±5.1 at last follow-up (P=0.001). One patient experienced persistent leg pain.

CONCLUSIONS

Lateral recess height and angle correlate with symptomatic lateral recess stenosis which is effectively treated utilizing interlaminar endoscopic lateral recess decompression.